Checksum

Arithmetic Cryptography

Synopsis

Calculates cryptographic and non-cryptographic checksums of field values.

Schema

- checksum:
    field: <ident>
    algorithm: <string>
    target_field: <string>
    output_format: <string>
    include_fields: <array>
    exclude_fields: <array>
    uppercase: <boolean>
    description: <text>
    if: <script>
    ignore_failure: <boolean>
    ignore_missing: <boolean>
    on_failure: <processor[]>
    on_success: <processor[]>
    tag: <string>

Configuration

The following fields are used to define the processor:

Field	Required	Default	Description
field	Y	-	Source field containing data to checksum
algorithm	Y	-	Checksum algorithm (crc32, crc64, adler32, fnv32, fnv64, fnv128, md5, sha1, sha256, sha512)
target_field	N	{field}_{algorithm}	Target field to store checksum result
output_format	N	hex	Output format (hex, base64, decimal)
include_fields	N	-	Array of fields to include for object checksums
exclude_fields	N	-	Array of fields to exclude from object checksums
uppercase	N	false	Output checksum in uppercase format
description	N	-	Explanatory note
if	N	-	Condition to run
ignore_failure	N	false	Continue processing if checksum calculation fails
ignore_missing	N	false	Skip processing if referenced field doesn't exist
on_failure	N	-	See Handling Failures
on_success	N	-	See Handling Success
tag	N	-	Identifier

Details

Calculates checksums using various algorithms ranging from simple CRC checksums to cryptographic hashes like SHA-256. The processor supports different data types including strings, byte arrays, objects, and arrays.

The processor handles multiple algorithm types including non-cryptographic checksums (CRC32, CRC64, Adler32, FNV variants) and cryptographic hashes (MD5, SHA-1, SHA-2 family). For object checksums, it can selectively include or exclude specific fields.

note

When calculating checksums for objects, fields are processed in alphabetical order to ensure consistent results. The processor formats object data as field:value pairs joined with pipes (|) for reliable checksum calculation.

The processor supports various output formats including hexadecimal (default), base64, and decimal. For large checksums, decimal format may fall back to hexadecimal representation to prevent overflow.

warning

MD5 and SHA-1 algorithms are considered cryptographically weak and should only be used for non-security purposes like data integrity verification or deduplication.

Examples

Basic File Checksum

Calculating SHA-256 checksum of file content...	{ "file_content": "Hello, World!" } - checksum: field: file_content algorithm: sha256 target_field: file_hash
generates cryptographic hash:	{ "file_content": "Hello, World!", "file_hash": "dffd6021bb2bd5b0af676290809ec3a53191dd81c7f70a4b28688a362182986f" }

Object Checksum with Field Selection

Creating checksum from specific object fields...	{ "user": { "id": 12345, "name": "john.doe", "email": "john@example.com", "password": "secret123", "last_login": "2024-01-15T10:30:00Z" } } - checksum: field: user algorithm: crc32 include_fields: ["id", "name", "email"] target_field: user_signature output_format: hex uppercase: true
calculates checksum from selected fields:	{ "user": {...}, "user_signature": "A3B7F2E1" }

Fast CRC Verification

Using fast CRC32 for data verification...	{ "packet_data": "Lorem ipsum dolor sit amet, consectetur adipiscing elit" } - checksum: field: packet_data algorithm: crc32 output_format: decimal target_field: data_crc
produces numeric CRC value:	{ "packet_data": "Lorem ipsum dolor sit amet, consectetur adipiscing elit", "data_crc": "2748146285" }

Array Content Checksum

Checksumming array data for deduplication...	{ "log_entries": [ "INFO: User logged in", "WARN: High memory usage", "ERROR: Database timeout" ] } - checksum: field: log_entries algorithm: fnv64 target_field: content_hash output_format: base64
generates content fingerprint:	{ "log_entries": [...], "content_hash": "qJdK8R9eFQA=" }

Configuration Integrity Check

Verifying configuration integrity with excluded sensitive fields...	{ "config": { "server": "prod-db-01", "port": 5432, "database": "analytics", "username": "analyst", "password": "secret", "ssl": true } } - checksum: field: config algorithm: sha1 exclude_fields: ["password"] target_field: config_checksum uppercase: true
creates integrity hash without sensitive data:	{ "config": {...}, "config_checksum": "8F4A5E2D9B3C6F1A7E8D4B2F9A1C5E7B8D2F4A6C" }